Anyone ever have a problem with these resetting themselves? I just acquired a yellow finger gorg and have been trying to lower my tank temp. I had it down until the weather changed, we turned the ac off and then it got hot towards the end of the day. The tank was back up to 79 before I turned on the ac. That was several days ago and I kept checking the temp but it was not getting lower. I checked the heater initially and it was still set at 76. This morning I checked the heater and it was set at 80 degrees so I turned it back down. Somehow it reset itself ...